|
|||||
|
|
Structural characterizations of Co2MnSi/MgO/Co2MnSi magnetic tunnel junctions by transmission electron microscopy |
|
| Authors: | TM Nakatani YK Takahashi M Yamamoto |
| Institution: | a Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-0047, Japan b National Institute for Materials Science, Tsukuba 305-0047, Japan c Division of Electronics for Informatics, Hokkaido University, Sapporo 060-0814, Japan |
| Abstract: | We have investigated the structure of Co2MnSi/MgO/Co2MnSi magnetic tunneling junctions with different tunnel magnetoresistance values depending on the in situ annealing temperatures just after the deposition of the upper Co2MnSi electrodes. The nano-beam diffraction patterns indicated that the degree of order of the upper Co2MnSi electrode annealed at 550 °C was higher than that of an electrode annealed at 400 °C. Moreover, the degree of the L21 order of the upper Co2MnSi electrode annealed at 550 °C was even lower than that of the lower Co2MnSi electrode annealed at an almost equal temperature of 600 °C. Atomic-scale observation using a high-angle annular dark-field (HAADF) method distinctly showed the existence of the L21-ordered regions in the B2-ordered matrix in the upper Co2MnSi electrode annealed at 400 °C. |
| Keywords: | Magnetic tunnel junction Co2MnSi Transmission electron microscopy HAADF-STEM |
| 本文献已被 ScienceDirect 等数据库收录！ | |